Field-Ready Reliability: Inspection, Spares, and the Pit Checklist

The mindset

Most matches are lost to reliability, not strategy. A robot that does one thing every match beats one that does three things sometimes. This lesson converts the prior failure modes into proactive habits.

The pre-match pit checklist

Run this before every match:

1. Battery : charged, >12.5 V resting, securely strapped, and the main Anderson connector tight, loose battery leads cause brownouts.
2. Fastener audit : wrench-check drivetrain, gearbox, and superstructure bolts. Re-seat anything backing out.
3. Pneumatics : charge the system, confirm the high side reaches system max and the regulated low side reads ~60 PSI, listen for leaks, and confirm the system holds with the compressor off.
4. Bumpers : within the legal mounting zone, numbers visible, hardware tight.
5. CAN/wiring : tug-test motor controller and CAN connectors; a wiggled CAN wire drops a device mid-match. Confirm no flashing fault LEDs.
6. Mechanism dry-run : in the pit, cycle every mechanism through its range and watch for binding or odd current draw.

Spare-parts kit (bring duplicates of failure-prone items)

• A charged spare battery (always more than one).
• Spare motor controllers and a spare motor of each type used.
• Pneumatic fittings, tubing, and a spare solenoid.
• Hex shaft stock, hex bearings (1/2 in hex), sprockets/belts, and assorted fasteners + nylocks.
• Blue threadlocker, zip ties, electrical tape, and spare Anderson connectors.

CAN and wiring discipline

• Strain-relieve every connector so vibration can’t unseat it.
• Keep CAN runs away from sharp edges and moving mechanisms; a pinched CAN wire kills the whole bus downstream.
• Label CAN IDs and keep a wiring map in the pit. (Remember: PDP and legacy CTRE PCM at CAN ID 0.)

Triage during an event

When something breaks between matches: reproduce it, look at the failed part to read the root cause (per the gearbox/fastener lesson), apply the matching fix, and re-test the full cycle before queueing again. Don’t ship an unverified fix to the field.

After the event

Keep a reliability log: what broke, the root cause, and the permanent fix. Teams that log failures stop repeating them season over season.

Key takeaways

• Reliability wins matches: run a fixed pre-match checklist covering battery, fasteners, pneumatics, bumpers, CAN/wiring, and a mechanism dry-run.
• Carry a spare-parts kit (extra batteries, motor controllers, fittings, hex shaft/bearings, threadlocker) for fast pit repairs.
• Strain-relieve and route CAN/wiring away from moving parts (PDP/PCM at CAN ID 0), and never send an unverified fix back to the field.

This lesson was adapted from learnfrc.com.